/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *  http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

/*
 * SPDX-License-Identifier: Apache-2.0
 */

#include <stdint.h>
#include <nffs/nffs.h>
#include <fs.h>
#include "nffs_test_utils.h"
#include <ztest.h>
#include <ztest_assert.h>

extern struct k_mem_slab nffs_block_entry_pool;

void test_gc_on_oom(void)
{
	int rc;

	/*** Setup. */
	/* Ensure all areas are the same size. */
	static const struct nffs_area_desc area_descs_two[] = {
		{ 0x00000000 + TEST_FLASH_OFFSET, 16 * 1024 },
		{ 0x00004000 + TEST_FLASH_OFFSET, 16 * 1024 },
		{ 0x00008000 + TEST_FLASH_OFFSET, 16 * 1024 },
		{ 0, 0 },
	};

	rc = nffs_format_full(area_descs_two);
	zassert_equal(rc, 0, "cannot format nffs");

	/* Leak block entries until only four are left. */
	/*
	 * XXX: This is ridiculous.  Need to fix nffs configuration so that the
	 * caller passes a config object rather than writing to a global
	 * variable.
	 */
	while (k_mem_slab_num_free_get(&nffs_block_entry_pool) != 4) {
		nffs_block_entry_alloc();
	}

	/*** Write 4 data blocks. */
	struct nffs_test_block_desc blocks[4] = { {
		.data = "1",
		.data_len = 1,
	}, {
		.data = "2",
		.data_len = 1,
	}, {
		.data = "3",
		.data_len = 1,
	}, {
		.data = "4",
		.data_len = 1,
	} };

	nffs_test_util_create_file_blocks("/myfile.txt", blocks, 4);

	zassert_equal(k_mem_slab_num_free_get(&nffs_block_entry_pool), 0,
							"file blocks problem");

	/* Attempt another one-byte write.  This should trigger a garbage
	 * collection cycle, resulting in the four blocks being collated.  The
	 * fifth write consumes an additional block, resulting in 2 out of 4
	 * blocks in use.
	 */
	nffs_test_util_append_file("/myfile.txt", "5", 1);

	zassert_equal(k_mem_slab_num_free_get(&nffs_block_entry_pool), 2,
							"file blocks problem");

	struct nffs_test_file_desc *expected_system =
		(struct nffs_test_file_desc[]) { {
			.filename = "",
			.is_dir = 1,
			.children = (struct nffs_test_file_desc[]) { {
				.filename = "myfile.txt",
				.contents = "12345",
				.contents_len = 5,
			}, {
				.filename = NULL,
			} },
		} };

	nffs_test_assert_system(expected_system, area_descs_two);
}